Dopamine excess in patients with head and neck paragangliomas.

AIM

This study aimed to determine the prevalence of excess dopamine in relation to clinical symptoms and nuclear imaging in head and neck paraganglioma (PGL) patients.

PATIENTS AND METHODS

Thirty-six consecutive patients with head and neck PGLs, evaluated between 1993 and 2009, were included. Clinical symptoms, dopamine excess (urinary 3-methoxytyramine (3-MT) or dopamine and/or plasma dopamine or 3-MT) and (nor)epinephrine excess (urinary (nor)metanephrine) as well as (111)In-octreotide and (123)I-metaiodobenzylguanide (MIBG) scintigraphy were documented.

RESULTS

Dopamine excess was found in seven patients (19.4%), but was unrelated to clinical signs and symptoms. Excretion of other catecholamines was unremarkable, except in one patient with adrenal pheochromocytoma. (123)I-MIBG uptake (present in 36.1% of patients) was associated with dopamine excess (p = 0.03).

CONCLUSION

Dopamine excess is present in a considerable percentage of patients with head and neck PGL, and its measurement may be useful in follow-up. Measurement of other catecholamines is necessary to rule out co-existent pheochromocytoma.